The diversity of terminals available on markets greatly enriches the personalized selections of user requirements. However, the diversity of terminals also causes great differences in terminal capabilities, such as screen size, color, and font. Even a single terminal varies dynamically in its capabilities with the insertion of a camera or the switch of Bluetooth. In order to enable the terminals to properly display contents such as browsed web pages and Multimedia Messaging Service (MMS), and to enable a server to most efficiently utilize the capabilities provided by the terminals, the related art provides a standardized representation of terminal capabilities and a corresponding method for identifying the terminal capabilities by the server, thereby enabling the server to adapt and provide for a user the contents that most match the user's mode, according to the terminal capabilities.
In the related art, in the case that a connection is established between a client and an origin server, or in the case that User Agent Profile (UAP) information representative of a terminal capability parameter concerning browsing capability has been updated, it is required to report UAP information to the sever. The processes for reporting UAP information in the above two cases will be illustrated, respectively.
FIG. 1 is a schematic diagram showing a process for reporting UAP information in the case that a connection is established between a client and a server, according to the related art.
Step 101: A UAP client initiates a browsing request containing the client terminal's UAP information, typically a Uniform Resource Locator (URL) of the UAP, to an origin server.
Step 102 to 103: The origin server initiates a request for obtaining the UAP to a UAP repository according to the URL of the UAP, and obtains the UAP.
Step 104: The origin server returns a response to the UAP client, and if the origin server may properly process the UAP information, the origin server returns information indicating successful reception of the UAP; otherwise, the origin server returns an error code.
The process shown in FIG. 1 only occurs in the initial stage of a session in which a connection is established between a client and a server side, and a session will be maintained between the server and the client until the server or the client switches off the connection. During this process, the server side may cache the client terminal's UAP information.
FIG. 2 is a schematic diagram showing a process for updating UAP information, according to the related art.
Step 201 to 202: After updating UAP information by a UAP client, the UAP client sends information indicating a change of capability information to an origin server.
Step 203 to 204: The origin server requests and obtains the changed UAP from a UAP repository, according to the received change information.
Step 205: The origin server returns a response to the UAP client, and if the origin server may properly process the UAP information, the origin server returns information indicative of the successful reception of the UAP; otherwise, the origin server returns an error code.
During the updating of the UAP information, the client notifies the server of such a change of its UAP via a Resume message. This occurs for multiple times during the browsing process of the terminal.
The above UAP is primarily used for adapting, in terms of contents, the capabilities of the server side and the client. As an example, in the case that the client wants to browse a web page, there are great differences in colors and display screen sizes supportable by terminals due to the diversity of terminal capabilities, and even for the same terminal, there are differences in the preferences of different users, such as font and whether to receive pictures on the web page. Accordingly, there is a need for a method for adapting terminal capabilities and user requirements by the server. The UAP provides a method for the server and the client to represent this and a means to deliver such a representation.
It can be seen from the above process that, due to the increasingly stronger terminal capabilities, there is a need for describing an increasingly larger amount of terminal device information, resulting in larger device capability description files, i.e. larger UAP files. Thus, it takes a long time to resolve the obtained UAP files, and a lot of network resources are occupied during transmission.
Moreover, due to the ever-increasing changes in the terminal device capabilities, the terminal device more frequently reports changed information to the server. It is a waste of network resources to transmit a part of the changed information that is not service-related.